Oxygen Sensor After Catalytic Converter, Checking Function
Oxygen Sensor after Catalytic Converter, Checking Function
• When servicing terminals in harness connector of oxygen sensor, use only gold-plated terminals.
Special tools, testers and auxiliary items required
• Multimeter (VAG1526) or Multimeter (VAG1715)
• Connector test kit (VAG1594)
• Wiring diagram
Test Prerequisites
• The respective fuses of Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) (G130) and Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) (G131) must be OK:
• Battery voltage must be at least 12.5 volts.
• Oxygen sensor heaters for oxygen sensors behind catalytic converter must be OK (no DTC entry).
• All electrical consumers such as, lights and rear window defroster must be switched off.
• Parking brake must be engaged or else daylight driving lights will be switched on.
• If vehicle is equipped with an A/C system, it must be switched off.
• Ground (GND) connections between engine and chassis must be OK.
• Exhaust system must be properly sealed between catalytic converter and cylinder head.
Function Test
- Coolant temperature must be at least 80 °C => [ Diagnostic Mode 01 - Read Current System Data ] Diagnostic Modes 01 - 09, Diagnostic mode 1: Check measured values; PID 5, Coolant temperature.
- Select the following output of oxygen sensor signals and check whether the specified values are being reached => [ Diagnostic Mode 05 - Read Oxygen Sensor Monitoring Test Results ] Diagnostic Modes 01 - 09, Diagnostic mode 5: Check output of oxygen sensor signals.
- Check specified values of the output of oxygen sensor signals at idle:
*) V = Voltage in Volts (oxygen sensor signal)
**) t = Time in seconds
Continuation for All Vehicles
• Cylinder bank 1 = in driving direction, right
• Cylinder bank 2 = in driving direction, left
If specified values are obtained:
- End diagnosis and switch ignition off.
If specified values are not obtained:
- End diagnosis and switch ignition off.
- Check signal wire and activation of oxygen sensor behind catalytic converter => [ Oxygen Sensors after Catalytic Converter, Checking Signal Wire and Activation ].